winrt: Use native file dialog

The native Windows Runtime file picker is required to support picking
of any file/folder from the system. Due to platform security restrictions,
the non-native file dialog is effectively useless when outside of the
application's installation or local storage directories.

This adds a QPA implementation for the WinRT file picker, as well as
a simple file system engine to handle files which were opened by the
picker. This necessary for platform security reasons, as it is not
possible to open files from arbitrary paths - only file handles opened by
the picker can be used, so these are kept inside this file system engine
and acted upon when a known path is observed.

The file system engine is only instantiated when needed, and may prove
useful for other areas of Qt (such as known folders/standard paths) which
must operate on a virtual file rather than an absolute path.

Task-number: QTBUG-37748
Change-Id: Ia4fd6c5065ac92101ce34adcb6c9026fbcff56df
Reviewed-by: Maurice Kalinowski <maurice.kalinowski@digia.com>

1 files changed, 8 insertions, 1 deletions

diff --git a/src/plugins/platforms/winrt/qwinrtservices.cpp b/src/plugins/platforms/winrt/qwinrtservices.cpp
index 6272b46f44..4ee2aa68f8 100644
--- a/src/plugins/platforms/winrt/qwinrtservices.cpp
+++ b/src/plugins/platforms/winrt/qwinrtservices.cpp
@@ -40,6 +40,7 @@
 ****************************************************************************/
 
 #include "qwinrtservices.h"
+#include "qwinrtfileengine.h"
 #include <QtCore/QUrl>
 #include <QtCore/QDir>
 #include <QtCore/QCoreApplication>
@@ -115,7 +116,13 @@ bool QWinRTServices::openDocument(const QUrl &url)
 
     HRESULT hr;
     ComPtr<IStorageFile> file;
-    {
+    ComPtr<IStorageItem> item = QWinRTFileEngineHandler::registeredFile(url.toLocalFile());
+    if (item) {
+        hr = item.As(&file);
+        if (FAILED(hr))
+            qErrnoWarning(hr, "Failed to cast picked item to a file");
+    }
+    if (!file) {
         const QString pathString = QDir::toNativeSeparators(url.toLocalFile());
         HStringReference path(reinterpret_cast<LPCWSTR>(pathString.utf16()), pathString.length());
         ComPtr<IAsyncOperation<StorageFile *>> op;